I'm checking how could I use this for registering children (non-profit family activity) as a group/family. They need to be able to enter a list of names, their type (parent/guardian/child) and other info in single pass, without having to create a WordPress User ID. The workflow is like:

1. Go to registration page.

2. Enter a full name, select a type and relevant info, repeat until we’ve entered the whole family. Alternatively, could be fixed name fields (maximum 7).

3. Upon submission, add each filled name into individual entry with same registration ID (could be the unique running ID of this plugin) and other common info (e.g. address, home phone).

It may have some similarity with earlier posts (e.g. How do I create multiple sign up forms?), not sure whether multiple form is needed in such scenario.

You're not too far off from what I want to do. As far as I can tell, there's no way to do this using the stock plugin.

I'm working on extending the plugin to support multiple "participant events" (i.e., a database that allows multiple different sign up groups) as well as custom display of the pdb_record pages based on parameters passed into the shortcode. No ETA on when I'll get through this though, as I have to get my own site working first. ;-)